1. Field of the Invention
This invention generally relates to a communication terminal for use in data communication, such as a facsimile machine, and in particular to a data communication terminal having a function of displaying the charge for using the terminal.
2. Description of the Prior Art
A facsimile machine is widely used as a data communication terminal. Recently, a facsimile machine is installed in a stationary store or the like to thereby provide a document transmission service for customers. In such a case, the service charge for transmitting a set of originals must be calculated on the basis of the communication time and the distance to the destination because the telephone charge varies depending on time and distance. As a result, the operator at the stationary store must measure the communication time expended for transmission of a set of originals and then consult with a charge schedule to calculate the telephone communication charge. And, then, a predetermined charge for using the facsimile machine is added to the telephone charge to arrive at the total service charge. In this manner, the operator at the stationary store is required not only to operate the facsimile machine, but also to go through calculations to determine the service charge each time, which is quite cumbersome. In addition, it is also disadvantageous for the customer because the service charge is unknown until the transmission has been completed.
Other than facsimile machines, teletex machines are also being used as communication terminals for providing information transmission service. In this case also, there are similar disadvantages.